This invention relates to a torque rod assembly adaptable for use in truck and bus applications. More particularly, the invention is directed to an improved, generally V-shaped torque rod assembly that allows elastomers to be used at both the apex end and opposite ends thereof.
While the invention is particularly directed to the art of vehicle suspension systems, and will be thus described with specific reference thereto, it will be appreciated that the invention may have usefulness in other fields and applications.
A suspension system for a truck or bus typically utilizes one of two types of torque rod assemblies to isolate the axle from the frame, provide lateral stability and provide axle alignment. Both types of assemblies are attached to the axle at one end and the vehicle frame at the other.
However, in the first type, a lateral rod attachment, torque rods are positioned fore and aft on both sides of the axle as well as laterally across the vehicle for stability. In the second type, a "V" assembly having a rigid apex end and a machined ball contained within a rigid spherical bushing is used. The bushing is typically retained within a metal ring. Two metal tubes, or subassemblies, are attached to the ring in a "V" configuration. At the opposite ends of the tubes, metal rings contain elastomer bushings with metal inner components. The "V" shape provides lateral stability and fore and aft isolation.
The main difficulty with the lateral rod attachment method is the costs associated with using three torque rods per axle. Further, there are some disadvantages associated with tight turning radii that make such systems undesirable for service where tight turns are anticipated. The axle pivot point varies depending upon axle articulation, causing hops and jerks and reducing bushing life at nonpivot locations.
The V-shaped configuration using the rigid apex is likewise very expensive. The rigid apex joint allows no independent articulation of the legs of the "V". Further, the apex joint is susceptible to deterioration and must be regularly lubricated.
Elastomer apex joints for the V-shaped configuration heretofore contemplated only single joints. Accordingly, these single joints could not withstand the forces involved, since the single elastomer apex joint carried double the load of the elastomers provided to the opposite ends of the apex joint.
The present invention contemplates a new and improved V-shaped torque rod assembly which resolves the above-referenced difficulties and others by, among other things, reducing the cost of the "V" type assembly, providing superior shock and vibration isolation by doubling the amount of elastomers at the apex, providing independent articulation of the "V" legs to improve ride, and reducing maintenance and service requirements.